Texas Instruments CD74HCT423M96G4

Overview

CD74HCT423M96G4 from Texas Instruments is a dual retriggerable monostable multivibrator with independent resets, designed for precise pulse generation and timing control in digital systems. It operates from 4.5 V to 5.5 V, features Schmitt-trigger inputs on both A and B trigger pins, supports trailing-edge (A) and leading-edge (B) triggering, and delivers buffered Q and Q̅ outputs. It is used in industrial control logic, debounce circuits, and programmable delay generators where external RC timing provides adjustable pulse widths from microseconds to seconds.

For engineers reviewing the CD74HCT423M96G4 datasheet, CD74HCT423M96G4 pinout, CD74HCT423M96G4 application, or CD74HCT423M96G4 equivalent, this page delivers verified electrical specs, SOIC-16 package details, timing behavior under -55°C to +125°C, reset-controlled pulse termination, and real-world design guidance for edge-triggered one-shot implementation.

Technical Context

The CD74HCT423M96G4 implements two independent monostable multivibrators, each with separate A (trailing-edge), B (leading-edge), and R (active-low reset) inputs. Triggering is retriggerable: a new input edge during an active output pulse extends the width, governed by t_W = 0.45 × R_XC_X at V_CC = 5 V. The device uses HCT logic, ensuring direct LSTTL input compatibility (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V) and CMOS-level output drive.

Each monostable includes Schmitt-trigger inputs for noise immunity, buffered complementary outputs (Q and Q̅), and independent reset capability that forces immediate low-state termination of the output pulse. Minimum external R_X is 5 kΩ; C_X can be as low as 0 pF. Pulse width matching between the two monos is ±2% under matched RC conditions.

Key Specifications

Pinout & Package

CD74HCT423M96G4 is housed in a 16-pin SOIC (D) package (JEDEC MS-012AC, 3.9 mm width), RoHS-compliant, with NIPDAU lead finish and moisture sensitivity level (MSL) 1 (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual monostable multivibrator applications.

Compared with CD74HCT123M96G4, the CD74HCT423M96G4 provides simpler level-sensitive reset behavior ideal for fault-clearing applications, while SN74HCT123DR offers enhanced manufacturability and statistical timing performance - making CD74HCT423M96G4 the optimal choice for ruggedized, long-lifecycle industrial and defense systems.

Availability

CD74HCT423M96G4 is available at Aetrix Electronics and suitable for industrial motor control, automotive sensor conditioning, test equipment timing, and power supply sequencing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HCT423M96G4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic ICs, with decades of heritage in high-reliability logic families.

The CD74HCT423M96G4 belongs to TI's CD74HCT logic series, engineered for robust operation in extreme environments and designed specifically for precision timing, signal conditioning, and industrial control applications demanding wide temperature tolerance and noise immunity.

FAQ

What is the key functional difference between CD74HCT423M96G4 and CD74HCT123M96G4?

The CD74HCT423M96G4 uses level-sensitive (active-low) reset inputs, whereas the CD74HCT123M96G4 accepts edge-triggered reset pulses (negative-to-positive transition). This makes CD74HCT423M96G4 more suitable for simple, latch-style reset control in safety-critical timing applications, while CD74HCT123M96G4 supports dynamic reset retriggering. Both share identical pinout, timing, and SOIC-16 packaging.

Can CD74HCT423M96G4 operate at 3.3 V?

No. CD74HCT423M96G4 is an HCT-family device specified only for 4.5 V to 5.5 V operation. Its input thresholds (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V) and output drive characteristics are optimized for 5 V LSTTL compatibility. For 3.3 V systems, consider HC-family variants like CD74HC423M96G4, which supports 2 V to 6 V but lacks LSTTL input compatibility.

How is output pulse width calculated for CD74HCT423M96G4?

The output pulse width t_W of CD74HCT423M96G4 is calculated as t_W = 0.45 × R_X × C_X, where R_X is the external timing resistor (minimum 5 kΩ) and C_X is the external timing capacitor (0 pF minimum). At V_CC = 5 V, this yields predictable timing - e.g., R_X = 100 kΩ and C_X = 100 nF gives t_W ≈ 4.5 ms. Accuracy depends on component tolerances and temperature drift.

Does CD74HCT423M96G4 support retriggering during an active output pulse?

Yes. CD74HCT423M96G4 is explicitly retriggerable: applying a valid edge (rising on B or falling on A) during an active Q output pulse extends the pulse width by another t_W interval. Retriggering is subject to minimum retrigger time (t_rT = 76 ns max at V_CC = 5 V, -55°C to +125°C), ensuring reliable extension without metastability.

What is the maximum fanout capability of CD74HCT423M96G4 outputs?

CD74HCT423M96G4 outputs support up to 10 LSTTL loads (standard outputs) or 15 LSTTL loads (bus driver mode, enabled via internal configuration not user-accessible). This fanout rating holds across the full operating temperature range (-55°C to +125°C) and ensures reliable signal integrity when driving multiple downstream logic inputs without external buffers.